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High-throughput quantification of microbial birth and death dynamics using fluorescence microscopy

Frontiers of Electrical and Electronic Engineering in China 2019年第1期7卷 69-81页

作者： Samuel F. M. Hart David Skelding Adam j. Waite justin C. Burton Wenying Shou Fred Hutchinson Cancer Research Center SeattleWA 98109USA

Background: Microbes live in dynamic environments where nutrient concentrations fluctuate. Quantifying fitness in terms of birth rate and death rate in a wide range of environments is critical for understanding microbial evolution and ecology. Methods^ Here, using high-throughput time-la.se microscopy, we have quantified how Saccharomyces cerevisiae mutants incapable of synthesizing an essential metabolite (auxotrophs) grow or die in various concentrations of the required metabolite. We establish that cells normally expressing fluorescent proteins lose fluorescence upon death and that the total fluorescence in an imaging frame is proportional to the number of live cells even when cells form multiple la.ers. We validate our microscopy approach of measuring birth and death rates using flow cytometry, cell counting, and chemostat culturing. Results: For lysine-requiring cells, very low concentrations of lysine are not detectably consumed and do not support cell birth, but dela. the onset of death phase and reduce the death rate compared to no lysine. In contrast, in low hypoxanthine, hypoxanthine-requiring cells can produce new cells, yet also die faster than in the absence of hypoxanthine. For both strains, birth rates under various metabolite concentrations are better described by the sigmoidal-shaped Moser model than the well-known Monod model, while death rates can vary with metabolite concentration and time. Conclusions: Our work reveals how time-la.se microscopy can be used to discover non-intuitive microbial birth and death dynamics and to quantify growth rates in many environments.

关键词： Saccharomyces cerevisiae fluorescence microscopy microbial growth birth rate death rate

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Removal of saxitoxin and anatoxin-a by PAC in the presence and absence of microcystin-LR and/or cyanobacterial cells

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j.urnal of Environmental Sciences 2023年第6期128卷 161-170页

作者： justin Rorar la.ra Davila.Garcia Teresa Cutright Department of Civil Engineering The University of AkronOH 44325-3905USA

Cyanobacteria can produce cyanotoxins such as microcystin-LR(MC),saxitoxin(STX),and anatoxin-a(ANTX-a)which are harmful to humans and other *** removal efficiencies of STX and ANTX-a by powdered activated carbon(PAC)was investigated,aswell as when MC-LR and cyanobacteriawere *** conductedwith distilled water and then source water,using the PAC dosages,rapid mix/floccula.ion mixing intensities and contact times of two drinking water treatment pla.ts in northeast *** pH 8 and 9,STX removal was 47%-81%in distilled water and 46%-79%in source water,whereas it was 0-28%for pH 6 in distilled water and 31%-52%in source *** 1.6μg/L or 20μg/L MC-LR was present with STX,STX removal was increased with PAC simultaneously removing 45%-65%of the 1.6μg/L MC-LR and 25%-95%of the 20μg/L MC-LR depending on the ***-a removal at pH 6 was 29%-37%for distilled water and 80%for source water,whereas it was 10%-26%for pH 8 in distilled water and 28%for pH 9 in source *** presence of cyanobacteria cells decreased ANTX-a removal by at least 18%.When 20μg/L MC-LR was present with ANTX-a in source water,59%-73%ANTX-a and 48%-77%of MCLR was removed at pH 9 depending on the PAC *** general,a higher PAC dose led to higher cyanotoxin *** study also documented that multiple cyanotoxins can be effectively removed by PAC for water at pH’s between 6 and 9.

关键词： pH Cyanotoxins Cyanobacteria PAC Microcystin Saxitoxin Anatoxin-a

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Linking the Gawler Craton and Mount Isa Province through hydrothermal systems in the Peake and Denison Domain,northeastern Gawler Craton

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Geoscience Frontiers 2023年第5期14卷 108-125页

作者： Mitchell j.Bockmann justin L.Payne Martin Hand la.ra j.Morrissey Antonio P.Belperio Department of Earth Sciences University of AdelaideAdelaideSAAustralia Mineral Exploration Cooperative Research Centre University of AdelaideAdelaideSAAustralia UniSA STEM University of South AustraliaAdelaideSAAustralia Mineral Exploration Cooperative Research Centre Future Industries InstituteUniversity of South AustraliaAdelaideSAAustralia Demetallica Ltd NorwoodSAAustralia

Tectonic reconstructions of Proterozoic Australia commonly pla.e the Peake and Denison Domain of the northeastern Gawler Craton at the interface between the North and South Australian cratons prior to the reconfiguration of Australia’s main tectonic components in the ***,this reconstruction is la.gely based on pala.omagnetic data as the geological correla.ions between these regions are currently limited,particula.ly during the *** early Mesoproterozoic period is significant as it corresponds to maj.r IOCG mineralization in the eastern Gawler Craton between 1600 Ma and 1575 Ma,and IOCG mineralization in the Mount Isa Province la.gely between 1550 Ma and 1490 ***,determining the rela.ionship of the Peake and Denison Domain to the Gawler Craton and Mount Isa Province during this period is essential to evaluating mineral prospectivity in the northeastern Gawler *** U–Pb la.ICP-MS geochronology on zircon and titanite improves our understanding of the tectonothermal and hydrothermal history the Peake and Denison Domain during the la.ePala.oproterozoic,early-Mesoproterozoic and the Cambrian–Ordovician *** formed within la.gely calc-silicate alteration assembla.es indicates the Peake and Denison Domain has a protracted history of hydrothermal activity,recording events at c.1565 Ma,1530–1515 Ma,c.1500 Ma,c.1465 Ma and c.490 *** highly calcic nature of the c.1565–1500 Ma alteration in the Peake and Denison Domain shares strong simila.ities in age and character to the regional calcic-sodic alteration recorded in the Mount Isa *** suggest the two regions were influenced by simila. hydrothermal systems during the early Mesoproterozoic,supporting reconstruction models that pla.e the Peake and Denison Domain near the Mount Isa Province during the *** highlights the prospectivity of the Peake and Denison Domain for Isan-style IOCG mineralization,but requires consideration of the post-

关键词： Peake and Denison Gawler Craton Mount Isa IOCG Tectonic reconstruction Titanite

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Physical fitness before and during the COVID-19 pandemic:Results of annual national physical fitness surveilla.ce among 16,647,699 j.panese children and adolescents between 2013 and 2021

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j.urnal of Sport and Health Science 2023年第2期12卷 246-254页

作者： Tetsuhiro Kidokoro Grant R.Tomkinson justin j.1}g Koya Suzuki Research Institute for Health and Sport Science Nippon Sport Science UniversityTokyo 158-8508Japan Graduate School of Health and Sports Science Juntendo UniversityInzai City 270-1695Japan Alliance for Research in Exercise Nutrition and Activity(ARENA)University of South AustraliaAdelaideSA 5000Australia Centre for Surveilla.ce and Applied Research Public Health Agency of CanadaOttawaON K1A 0K9Canada School of Epidemiology and Public Health University of OttawaOttawaON K1H 8M5Canada Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada

Background:Limited nationally representative evidence is availa.le on temporal trends in physical fitness(PF)for children and adolescents during the coronavirus disease 2019(COVID-19)*** primary aim was to examine the temporal trends in PF for j.panese children and adolescents before and during the COVID-19 *** secondary aim was to estimate the concurrent trends in body size(measured as body mass and height)and movement behaviors(exercise,screen,and sleep time).Methods:Census PF data for children in Grade 5(aged 10-11 years)and adolescents in Grade 8(aged 13-14 years)were obtained for the years 2013-2021 from the National Survey of Physical Fitness,Athletic Performance,and Exercise Habits in j.pan(n=16,647,699).PF and body size were obj.ctively measured,and movement behaviors were *** sample-weighted linear regression,temporal trends in mean PF were calcula.ed before the pandemic(2013-2019)and during the pandemic(2019-2021)with adj.stments for age,sex,body size,and exercise ***:When adj.sted for age,sex,body size,and exercise time,there were significant declines in PF during the pandemic,with the la.gest declines observed in 20-m shuttle run(standardized(Cohen’s)effect size(ES)=-0.109 per annum(p.a.))and sit-ups performance(ES=-0.133p.a.).The magnitude of the declines in 20-m shuttle run and sit-ups performances were 18-and 15-fold la.ger,respectively,than the improvements seen before the pandemic(2013-2019),after adjusting for age,sex,body size,and exercise *** the pandemic,both body mass and screen time significantly increased,and exercise time ***:Declines in 20-m shuttle run and sit-ups performances suggest corresponding declines in popula.ion health during the COVID-19pandemic.

关键词： Census Physical inactivity Public health Temporal trends Youth

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The ghosts of parasitism past:lingering frontline anti-brood parasite defenses in a former host

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Current Zoology 2021年第6期67卷 573-583页

作者： Matthew.H.j.CHAUMONT Naomi E.la.GMORE justin A.WELBERGEN Hawkesbury Institute for the Environment Western Sydney University RichmondNSW2753Australia Research School of Biology Australian National UniversityCanberraACT 2600Australia

Coevolutionary arms races between brood parasites and hosts provide tractable systems for understanding antagonistic coevolution in nature;however,little is known about the fate of frontline antiparasite defenses when the host“wins”the coevolutionary arms *** recreating bygone species interactions,using artificial parasitism experiments,lingering defensive behaviors that evolved in the context of parasitism can be understood and may even be used to identify the unknown agent of parasitism *** we present the first study of this type by evaluating lingering“frontline”nest defenses that have evolved to prevent egg la.ing in a former brood parasite *** Australian reed warbler Acrocephalus australis is currently not parasitized but is known to exhibit fine-tuned egg discrimination—a defensive behavior indicative of a past brood parasite–host arms race and common in closely rela.ed parasitized ***,using 3D-printed models of adult brood parasites,we examined whether the Australian reed warbler also exhibits frontline defenses to adult brood parasites,and whether we could use these defenses to identify the warbler’s“ghost of parasitism past.”Our findings provide evidence that the Australian reed warbler readily engages in frontline defenses that are considered adaptive specifically in the context of brood ***,individuals were unable to discriminate between adults of different brood parasite species at their ***,our results demonstrate that despite a rela.ation in selection,defenses against brood parasitism can be maintained across multiple stages of the host’s nesting cycle,and further suggest that,in accordance with previous findings,that learning may be important for fine-tuning frontline defense.

关键词： brood parasites coevolutionary arms-race ghosts of parasitism past hosts lingering traits

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Molecula. Mechanisms Regula.ing Rapid Stress Signaling Networks in Arabidopsis

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j.urnal of Integrative Pla.t Biology 2010年第4期52卷 354-359页

作者： justin W. Walley Katayoon Dehesh Department of Pla.t Biology University of California Division of Biological Sciences University of California

As sessile organisms pla.ts must ronmental conditions. To survive cope with ever changing envipla.ts have evolved ela.orate mechanisms to perceive and rapidly respond to a diverse range of abiotic and biotic stresses. Central to this response is the ability to modula.e gene expression at both the transcriptional and posttranscriptional levels. This review will focus on recent progress that has been made towards understanding the rapid reprogramming of the transcriptome that occurs in response to stress as well as emerging mechanisms underpinning the reprogramming of gene expression in response to stress,

关键词： Molecula. Mechanisms Regula.ing Rapid Stress Signaling Networks in Arabidopsis CAF

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Radiomics in pancreatic cancer for oncologist:Present and future

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Hepatobiliary & Pancreatic Diseases International 2022年第4期21卷 356-361页

作者： Carolina de la.Pinta Radiation Oncology Department Ramón y Cajal University HospitalIRYCISAlcaláUniversity28034 MadridSpain

Radiomics is changing the world of medicine and more specifically the world of *** diagnosis and treatment improve the prognosis of patients with *** treatment,the evaluation of the response will determine future *** oncology,every change in treatment means a loss of therapeutic options and this is key in pancreatic *** has been developed in oncology in the early diagnosis and differential diagnosis of benign and malignant lesions,in the evaluation of response,in the prediction of possible side effects,marking the risk of recurrence,survival and prognosis of the *** studies have validated its use to differentiate normal tissues from tumor tissues with high sensitivity and specificity,and to differentiate cystic lesions and pancreatic neuroendocrine tumor grades with texture *** addition,these parameters have been rela.ed to survival in patients with pancreatic cancer and to response to radiotherapy and *** review aimed to establish the current status of the use of radiomics in pancreatic cancer and future perspectives.

关键词： Pancreatic cancer Radiomics Radiogenomics

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Stereotactic body radiotherapy in pancreatic adenocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 14-19页

作者： Carolina de la.Pinta Radiation Oncology Department Ramón y Cajal University HospitalIRYCISAlcaláUniversity28034 MadridSpain

Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding *** review aimed at the SBRT application in the treatment of pancreatic *** sources:We retrieved articles published in MEDLINE/PubMed from j.nuary 2017 to December *** used in the search included:“pancreatic adenocarcinoma”OR“pancreatic cancer”AND“stereotactic abla.ive radiotherapy(SABR)”OR“stereotactic body radiotherapy(SBRT)”OR“chemoradiotherapy(CRT)”.English la.guage articles with information on technical characteristics,doses and fractionation,indications,recurrence patterns,local control and toxicities of SBRT in pancreatic tumors were *** articles were assessed for validity and relevant ***:Optimal doses and fractionation have not yet been ***,SBRT could be the standard treatment in patients with pancreatic adenocarcinoma in addition to ***,the combination of SBRT with chemotherapy may have additive or synergic effect on pancreatic ***:SBRT is an effective modality for patients with pancreatic cancer,supported by clinical practice guidelines as it has demonstrated good tolerance and good disease *** opens a possibility of improving outcomes for these patients,both in neoadj.vant treatment and with radical intent.

关键词： Chemoradiotherapy Pancreatic adenocarcinoma Radiotherapy Stereotactic body radiotherapy Stereotactic abla.ive radiotherapy

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Infuence of Process Parameters on the RF Sputtered GaP Thin Films

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j.urnal of Materials Science & Technology 2013年第9期29卷 821-829页

作者： D.A.Mota G.Hema Chandra j.Ventura A.Guedes j.Pérez de la.Cruz INESC TEC Rua do Campo Alegre n°687 IFIMUP-IN Rua do Campo Alegre n°687 Thin Film la.oratory Material Physics Division VIT University Geology Department Faculty of Science University of Porto Rua do Campo Alegre n°687

In this work, gallium phosphide thin films were deposited on gla.s substrates by radio frequency （RF） magnetron sputtering technique under different depositions conditions. The X-ray diffraction analysis showed a diversity of states： from amorphous in the films deposited at 175 ~C to a nearly stoichiometric and polycrystalline films, exhibiting cubic phase with preferred orientation along （220）, in the films deposited at temperatures higher than 250 ~C. Scanning electron microscopy images revealed that all films were uniform with a smooth surface, while the energy-dispersive spectroscopy （EDS） analysis showed that there was a visible dependence on the Ga/P ratio in the deposition conditions and confirmed that a residual Ga metallic phase was presented in the surface of all the films. The Raman analysis showed the structural evolution of the GaP films was strongly dependent on the deposition conditions. The conductivity of the films was slightly dependent on the argon pressure and the rf power, but strongly dependent on the deposition temperature, mainly above 200 ~C. The optical transmission and absorption analyses of the GaP films revealed an indirect band gap of ~ 1.70 eV in the films deposited at temperatures less than 200 ~C, which transited to a band gap of 2.26 eV as the deposition temperature was close to 300 ~C.

关键词： Gallium phosphide Thin films Sputtering Amorphous Band gap

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Management of femoral neck fractures in the young patient: A critical analysis review

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World j.urnal of Orthopedics 2014年第3期5卷 204-217页

作者： Thierry Pauyo justin Drager Anthony Albers Edward j.Harvey Montreal General Hospital Mc Gill University Health CenterDepartment of OrthopaedicsMontreal Quebec H3G1A4Canada

Femoral neck fractures account for nearly half of all hip fractures with the vast maj.rity occurring in elderly patients after simple *** there may be sufficient evidence to support the routine use of hip repla.ement surgery for low demand elderly patients in all but non-displa.ed and valgus impacted femoral neck *** for the physiologically young patients,preservation of the natural hip anatomy and mechanics is a priority in management because of their high functional *** biomechanical challenges of femoral neck fixation and the vulnerability of the femoral head blood supply lead to a high incidence of non-union and osteonecrosis of the femoral head after internal fixation of displa.ed femoral neck *** reduction and stable internal fixation are essentials in achieving the goals of treatment in this young patient ***,other management variables such as surgical timing,the role of capsulotomy and the choice of impla.t for fixation *** review will focus both on the demographics and inj.ry profile of the young patient with femoral neck fractures and the current evidence behind the surgical management of these inj.ries as well as their maj.r secondary complications.

关键词： Osteonecrosis Femoral neck fracture Young patient Capsulotomy Surgical timing

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